In this new edition of Terrorism and Counterterrorism: Understanding the New Security Environment, Readings and Interpretations, Brigadier General (Retired) Russell Howard and Dr. Bruce Hoffman have collected original and previously published seminal articles and essays by political scientists, government officials, and members of the nation's armed forces. The editors and several of the authors write from practical field experience in the nation's war on terrorism. Others have had significant responsibility for planning government policy and responses. The contributors include a majority of the significant names in the field including John Arquilla, Richard Betts, Martha Crenshaw, Rohan Gunaratna, Richard Shultz, and Paul Pillar. Unit I of the book analyzes the philosophical, political, and religious roots of terrorist activities around the world and discusses the national, regional, and global effects of historical and recent acts of terrorism. In addition to material on the threats from suicide bombers, as well as chemical, biological, radiological, and nuclear weapons, there are also important contributions analyzing new and growing threats such as genomic terrorism. Unit II deals with past, present, and future national and international responses to--and defenses against--terrorism. Essays and articles in this section analyze and debate the practical, political, ethical, and moral questions raised by military and non-military responses (and pre-emptive actions) outside of the context of declared war. This section has expanded on the previous edition to include expanded strategic and tactical counterterrorism offerings and a final chapter devoted entirely to the post-bin Laden security environment.